Localization services in optical fiber-based distributed communications components and systems, and related methods

ABSTRACT

Optical fiber-based distributed communications components and systems, and related methods to provide localization services for client devices are disclosed. The localization services allow the providing and/or determination of the location of client devices in communication with a component or components of the optical fiber-based distributed communications system. The location of client devices can be provided and/or determined based on knowledge of the location of the component or components in the optical fiber-based distributed communications system in communication with the client device. This information can be used to determine or provide a more precise area of location or area of location for client devices. The optical fiber-based distributed communications components and systems, and related methods disclosed herein may be well-suited for indoor environments where other methods of providing and/or determining location of client devices may be obstructed or not possible due to the indoor environment.

PRIORITY APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 13/628,497 filed Sep. 27, 2012, now issued as U.S.Pat. No. 8,983,301, which claims priority to International ApplicationNo. PCT/US11/29895 filed Mar. 25, 2011, which claims the benefit ofpriority to U.S. Provisional Patent Application Ser. No. 61/319,659filed Mar. 31, 2010, the contents of which are relied upon andincorporated herein by reference in their entireties.

BACKGROUND

Field of the Disclosure

The technology of the disclosure relates to optical fiber-baseddistributed communications systems for distributing radio-frequency (RF)signals over optical fiber to remote antenna units, and related controlsystems and methods.

Technical Background

Wireless communication is rapidly growing, with ever-increasing demandsfor high-speed mobile data communication. As an example, so-called“wireless fidelity” or “WiFi” systems and wireless local area networks(WLANs) are being deployed in many different types of areas (e.g.,coffee shops, airports, libraries, etc.). Distributed communicationssystems communicate with wireless devices called “clients,” which mustreside within the wireless range or “cell coverage area” in order tocommunicate with an access point device.

One approach to deploying a distributed communications system involvesthe use of radio frequency (RF) antenna coverage areas, also referred toas “antenna coverage areas.” Antenna coverage areas can have a radius inthe range from a few meters up to twenty meters as an example. Combininga number of access point devices creates an array of antenna coverageareas. Because the antenna coverage areas each cover small areas, thereare typically only a few users (clients) per antenna coverage area. Thisallows for minimizing the amount of bandwidth shared among the wirelesssystem users. It may be desirable to provide antenna coverage areas in abuilding or other facility to provide distributed communications systemaccess to clients within the building or facility. However, it may bedesirable to employ optical fiber to distribute communication signals.Benefits of optical fiber include increased bandwidth.

One type of distributed communications system for creating antennacoverage areas, called “Radio-over-Fiber” or “RoF,” utilizes RF signalssent over optical fibers. Such systems can include a head-end stationoptically coupled to a plurality of remote antenna units that eachprovide antenna coverage areas. The remote antenna units can eachinclude RF transceivers coupled to an antenna to transmit RF signalswirelessly, wherein the remote antenna units are coupled to the head-endstation via optical fiber links. The RF transceivers in the remoteantenna units are transparent to the RF signals. The remote antennaunits convert incoming optical RF signals from the optical fiber link toelectrical RF signals via optical-to-electrical (O/E) converters, whichare then passed to the RF transceiver. The RF transceiver converts theelectrical RF signals to electromagnetic signals via antennas coupled tothe RF transceiver provided in the remote antenna units. The antennasalso receive electromagnetic signals (i.e., electromagnetic radiation)from clients in the antenna coverage area and convert them to electricalRF signals (i.e., electrical RF signals in wire). The remote antennaunits then convert the electrical RF signals to optical RF signals viaelectrical-to-optical (E/O) converters. The optical RF signals are thensent to the head-end station via the optical fiber link.

It may be desired to provide such optical fiber-based distributedcommunications systems indoors, such as inside a building or otherfacility, to provide indoor wireless communication for clients.Otherwise, wireless reception may be poor or not possible for wirelesscommunication clients located inside the building. In this regard, theremote antenna units can be distributed throughout locations inside abuilding to extend wireless communication coverage throughout thebuilding. Other services may be negatively affected or not possible dueto the indoor environment. For example, it may be desired or required toprovide localization services for a client, such as emergency 911 (E911)services as an example. If the client is located indoors, techniquessuch as global positioning services (GPSs) may not be possible toprovide or determine the location of the client. Further, triangulationtechniques from the outside network may not be able to determine thelocation of the client.

SUMMARY OF THE DETAILED DESCRIPTION

Embodiments disclosed in the detailed description include opticalfiber-based distributed communications components and systems, andrelated methods to provide localization services for client devices. Thelocalization services allow the providing and/or determination of thelocation of client devices in communication with a component orcomponents of the optical fiber-based distributed communications system.The location of client devices can be provided and/or determined basedon knowledge of the location of the component or components in theoptical fiber-based distributed communications system in communicationwith the client device. In this scenario, the client device would beknown to be within communication range of such component or components.This information can be used to determine or provide a more precise areaof location of the client device. The optical fiber-based distributedcommunications components and systems, and related methods disclosedherein may be well-suited for indoor environments where other methods ofproviding and/or determining the location of client devices may beobstructed or not possible due to the indoor environment.

In this regard, in certain embodiments disclosed herein, distributedcommunications equipment is provided. The distributed communicationsequipment supports optical fiber-based distributed communicationsservices. The distributed communications apparatus in this embodimentalso supports providing a signal used for determining the location ofclient devices (also referred to herein as “tracking signal”) to remoteantenna units (RAUs) configured to provide communications with clientdevices. The tracking signal may be generated by a tracking signalgenerator or pilot or beacon generator, as examples. The tracking signalis a unique signal that can be associated to a particular location orzone in the optical fiber-based distributed communications system. Thelocation of the client device can be determined by correlating clientdevice identification information with the ability of the client deviceto receive the tracking signal. The location of the client device can bedetermined by the distributed communications apparatus or otherprocessing units coupled to the distributed communications apparatusover a network.

In this regard, the distributed communications apparatus includes atleast one first downlink input configured to receive downlink electricalradio frequency (RF) communications signals. The distributedcommunications apparatus also includes at least one uplink outputconfigured to receive and communicate uplink electrical RFcommunications signals from a communications uplink. The distributedcommunications apparatus also includes at least one optical interface(OI) configured to receive and convert the downlink electrical RFcommunications signals into downlink optical RF communications signalsto be provided to at least one RAU, and receive and convert uplinkoptical RF communications signals from at least one RAU on thecommunications uplink into uplink electrical RF communications signalsprovided to the at least one uplink output. The distributedcommunications apparatus also includes at least one second downlinkinput configured to receive at least one electrical tracking signal. Theat least one OI is further configured to receive and convert the atleast one electrical tracking signal into at least one optical trackingsignal to be provided to at least one RAU. The distributedcommunications apparatus may be configured to not split or combine thetracking signal so that the uniqueness of the correlation of thetracking signal to a particular component or components in the opticalfiber-based distributed communications system is not lost and isretained. Related methods are also disclosed.

In other embodiments, a distributed communications apparatus is providedthat is configured to support receiving client device identificationinformation as uplink communication data from an RAU without receivingand providing a tracking signal to the RAU. By knowing and correlatingthe location of particular components within the optical fiber-baseddistributed communications system, the distributed communicationsapparatus and/or other systems coupled to the distributed communicationsapparatus over a network are able to determine and/or provide thelocation of the client device. The component or components with whichthe client device is in communication can be associated withidentification information of the client device.

In this regard, the distributed communications apparatus includes atleast one first downlink input configured to receive downlink electricalRF communications signals. The distributed communications apparatus alsoincludes at least one uplink output configured to receive andcommunicate uplink electrical RF communications signals from acommunications uplink. The distributed communications apparatus alsoincludes an OI configured to receive and convert the downlink electricalRF communications signals into downlink optical RF communicationssignals to be provided to at least one RAU, and receive and convertuplink optical RF communications signals that include client deviceidentification information from the at least one RAU on thecommunications uplink into uplink electrical RF communications signalsprovided to the at least one uplink output. To retain thedistinctiveness of communications from the components in the opticalfiber-based communications system for providing localization services,the distributed communications apparatuses may, for example, beconfigured to not split or combine uplink electrical RF communicationsignals from an RAU among the plurality of RAUs with uplink electricalRF communication signals from another RAU among the plurality of RAUs.Alternatively, the distributed communications apparatus may, forexample, be configured to not split or combine the uplink electrical RFcommunication signals from the OI with uplink electrical RFcommunication signals from another OI.

Additional features and advantages will be set forth in the detaileddescription which follows, and in part will be readily apparent to thoseskilled in the art from that description or recognized by practicing theembodiments as described herein, including the detailed description thatfollows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description present embodiments, and are intendedto provide an overview or framework for understanding the nature andcharacter of the disclosure. The accompanying drawings are included toprovide a further understanding, and are incorporated into andconstitute a part of this specification. The drawings illustrate variousembodiments, and together with the description serve to explain theprinciples and operation of the concepts disclosed.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic diagram of an exemplary optical fiber-baseddistributed communications system;

FIG. 2 is a partially schematic cut-away diagram of an exemplarybuilding infrastructure in which an optical fiber-based distributedcommunications system is employed;

FIG. 3 is an exemplary schematic diagram of exemplary head-end equipmentin the form of a head-end unit (HEU) deployed in the optical fiber-baseddistributed communications system of FIGS. 1 and 2;

FIG. 4 is a schematic diagram of an exemplary optical fiber-baseddistributed communications system configured to communicate trackingsignals to tracking remote antenna units (RAUs) to provide localizationservices for client devices;

FIG. 5A is a schematic diagram of exemplary alternative head-endequipment configured to provide tracking signals to tracking RAUs tosupport providing localization services for client devices;

FIG. 5B is a schematic diagram of other exemplary alternative head-endequipment configured to provide tracking signals to tracking RAUs tosupport providing localization services for client devices;

FIG. 6 is a schematic diagram of other exemplary alternative head-endequipment configured to provide communication signals to RAUs andtracking signals to tracking RAUs to support providing localizationservices for client devices;

FIG. 7 is a schematic diagram of the head-end equipment in FIG. 6provided in an optical fiber-based distributed communications system ina building containing at least one tracking RAU per floor;

FIG. 8 is a schematic diagram of a fiber optic cable containing downlinkand uplink optical fibers connected between an optical interface card(s)(OIC(s)) and RAUs, wherein an RAU and tracking RAU share a commonantenna;

FIG. 9 is a schematic diagram of other exemplary alternative head-endequipment configured to provide communication signals to RAUs andtracking signals to tracking RAUs to support providing localizationservices for client devices;

FIG. 10 is a schematic diagram of an exemplary optical interface card(OIC) adapted and configured to support providing localization servicesfor client devices on a per-OIC resolution in an optical fiber-baseddistributed communications system; and

FIG. 11 is a schematic diagram of an exemplary OIC adapted andconfigured to support providing localization services for client deviceson a per-RAU resolution in an optical fiber-based distributedcommunications system.

DETAILED DESCRIPTION

Reference will now be made in detail to the embodiments, examples ofwhich are illustrated in the accompanying drawings, in which some, butnot all embodiments are shown. Indeed, the concepts may be embodied inmany different forms and should not be construed as limiting herein;rather, these embodiments are provided so that this disclosure willsatisfy applicable legal requirements. Whenever possible, like referencenumbers will be used to refer to like components or parts.

Embodiments disclosed in the detailed description include opticalfiber-based distributed communications components and systems, andrelated methods to provide localization services for client devices. Thelocalization services allow the providing and/or determination of thelocation of client devices in communication with a component orcomponents of the optical fiber-based distributed communications system.The location of client devices can be provided and/or determined basedon knowledge of the location of the component or components in theoptical fiber-based distributed communications system in communicationwith the client device. In this scenario, the client device would beknown to be within communication range of such component or components.This information can be used to determine or provide a more precise areaof location of the client device. The optical fiber-based distributedcommunications components and systems, and related methods disclosedherein may be well-suited for indoor environments where other methods ofproviding and/or determining the location of client devices may beobstructed or not possible due to the indoor environment.

Before discussing the exemplary components, systems, and methods ofproviding localization services in an optical fiber-based distributedcommunications system, which starts at FIG. 4, an exemplary generalizedoptical fiber-based distributed communications is first described withregard to FIGS. 1-3. In this regard, FIG. 1 is a schematic diagram of ageneralized embodiment of an optical fiber-based distributedcommunications system. In this embodiment, the system is an opticalfiber-based distributed communications system 10 that is configured tocreate one or more antenna coverage areas for establishingcommunications with wireless client devices located in the radiofrequency (RF) range of the antenna coverage areas. In this regard, theoptical fiber-based distributed communications system 10 includeshead-end equipment, exemplified as a head-end unit or HEU 12, one ormore remote antenna units (RAUs) 14 and an optical fiber link 16 thatoptically couples the HEU 12 to the RAU 14. The HEU 12 is configured toreceive communications over downlink electrical RF signals 18D from asource or sources, such as a network or carrier as examples, and providesuch communications to the RAU 14. The HEU 12 is also configured toreturn communications received from the RAU 14, via uplink electrical RFsignals 18U, back to the source or sources. In this regard, in thisembodiment, the optical fiber link 16 includes at least one downlinkoptical fiber 16D to carry signals communicated from the HEU 12 to theRAU 14 and at least one uplink optical fiber 16U to carry signalscommunicated from the RAU 14 back to the HEU 12.

The optical fiber-based wireless system 10 has an antenna coverage area20 that can be substantially centered about the RAU 14. The antennacoverage area 20 of the RAU 14 forms an RF coverage area 21. The HEU 12is adapted to perform or to facilitate any one of a number ofRadio-over-Fiber (RoF) applications, such as radio-frequency (RF)identification (RFID), wireless local-area network (WLAN) communication,or cellular phone service. Shown within the antenna coverage area 20 isa client device 24 in the form of a mobile device as an example, whichmay be a cellular telephone as an example. The client device 24 can beany device that is capable of receiving RF communication signals. Theclient device 24 includes an antenna 26 (e.g., a wireless card) adaptedto receive and/or send electromagnetic RF signals.

With continuing reference to FIG. 1, to communicate the electrical RFsignals over the downlink optical fiber 16D to the RAU 14, to in turn becommunicated to the client device 24 in the antenna coverage area 20formed by the RAU 14, the HEU 12 includes an electrical-to-optical (E/O)converter 28. The E/O converter 28 converts the downlink electrical RFsignals 18D to downlink optical RF signals 22D to be communicated overthe downlink optical fiber 16D. The RAU 14 includes anoptical-to-electrical (O/E) converter 30 to convert received downlinkoptical RF signals 22D back to electrical RF signals to be communicatedwirelessly through an antenna 32 of the RAU 14 to client devices 24located in the antenna coverage area 20.

Similarly, the antenna 32 is also configured to receive wireless RFcommunications from client devices 24 in the antenna coverage area 20.In this regard, the antenna 32 receives wireless RF communications fromclient devices 24 and communicates electrical RF signals representingthe wireless RF communications to an E/O converter 34 in the RAU 14. TheE/O converter 34 converts the electrical RF signals into uplink opticalRF signals 22U to be communicated over the uplink optical fiber 14U. AnO/E converter 36 provided in the HEU 12 converts the uplink optical RFsignals 22U into uplink electrical RF signals, which can then becommunicated as uplink electrical RF signals 18U back to a network orother source. The HEU 12 in this embodiment is not able to distinguishthe location of the client devices 24 in this embodiment. The clientdevice 24 could be in the range of any antenna coverage area 20 formedby an RAU 14.

To provide further exemplary illustration of how an optical fiber-baseddistributed communications system can be deployed indoors, FIG. 2 is apartially schematic cut-away diagram of a building infrastructure 40employing the optical fiber-based distributed communications system 10of FIG. 1. The building infrastructure 40 generally represents any typeof building in which the optical fiber-based distributed communicationssystem 10 can be deployed. As previously discussed with regard to FIG.1, the optical fiber-based distributed communications system 10incorporates the HEU 12 to provide various types of communicationservices to coverage areas within the building infrastructure 40, as anexample. For example, as discussed in more detail below, the opticalfiber-based distributed communications system 10 in this embodiment isconfigured to receive wireless radio-frequency (RF) signals and convertthe RF signals into Radio-over-Fiber (RoF) signals to be communicatedover the optical fiber link 16 to the RAUs 14. The optical fiber-baseddistributed communications system 10 in this embodiment can be, forexample, an indoor distributed antenna system (IDAS) to provide wirelessservice inside the building infrastructure 40. These wireless signalscan include, but are not limited to, cellular service, wireless servicessuch as RFID tracking, Wireless Fidelity (WiFi), local area network(LAN), and combinations thereof, as examples.

With continuing reference to FIG. 2, the building infrastructure 40includes a first (ground) floor 42, a second floor 44, and a third floor46. The floors 42, 44, 46 are serviced by the HEU 12 through a maindistribution frame 48, to provide antenna coverage areas 50 in thebuilding infrastructure 40. Only the ceilings of the floors 42, 44, 46are shown in FIG. 2 for simplicity of illustration. In the exampleembodiment, a main cable 52 has a number of different sections thatfacilitate the placement of a large number of RAUs 14 in the buildinginfrastructure 40. Each RAU 14 in turn services its own coverage area inthe antenna coverage areas 50. The main cable 52 can include, forexample, a riser section 54 that carries all of the downlink and uplinkoptical fibers 16D, 16U to and from the HEU 12. The main cable 52 caninclude one or more multi-cable (MC) connectors adapted to connectselect downlink and uplink optical fibers 16D, 16U, along with anelectrical power line, to a number of optical fiber cables 56.

The main cable 52 enables multiple optical fiber cables 56 to bedistributed throughout the building infrastructure 40 (e.g., fixed tothe ceilings or other support surfaces of each floor 42, 44, 46) toprovide the antenna coverage areas 50 for the first, second and thirdfloors 42, 44 and 46. In an example embodiment, the HEU 12 is locatedwithin the building infrastructure 40 (e.g., in a closet or controlroom), while in another example embodiment the HEU 12 may be locatedoutside of the building infrastructure 40 at a remote location. A basetransceiver station (BTS) 58, which may be provided by a second partysuch as a cellular service provider, is connected to the HEU 12, and canbe co-located or located remotely from the HEU 12. A BTS is any stationor source that provides an input signal to the HEU 12 and can receive areturn signal from the HEU 12. In a typical cellular system, forexample, a plurality of BTSs are deployed at a plurality of remotelocations to provide wireless telephone coverage. Each BTS serves acorresponding cell and when a mobile station enters the cell, the BTScommunicates with the mobile station. Each BTS can include at least oneradio transceiver for enabling communication with one or more subscriberunits operating within the associated cell.

To provide further detail on the components of the exemplary HEU 12provided in the optical fiber-based distributed communications system 10of FIGS. 1 and 2, FIG. 3 is provided. FIG. 3 is a schematic diagram ofthe HEU 12 to provide further detail. As illustrated therein, the HEU 12in this embodiment includes a head-end controller (HEC) 60 that managesthe functions of the HEU 12 components and communicates with externaldevices via interfaces, such as a RS-232 port 62, a Universal Serial Bus(USB) port 64, and an Ethernet port 68, as examples. The HEU 12 can beconnected to a plurality of BTSs, transceivers, and the like via inputs70, which may be BTS inputs or other inputs, and outputs 72, which maybe BTS outputs or other outputs The inputs 70 are downlink connectionsand the outputs 72 are uplink connections, which can be provided insingle connectors or together in a duplex connector. Each input 70 isconnected to a downlink BTS interface card (BIC) 74 located in the HEU12, and each output 72 is connected to an uplink BIC 76 also located inthe HEU 12. The downlink BIC 74 is configured to receive incoming ordownlink RF signals from the inputs 70 and split the downlink RF signalsinto copies to be communicated to the RAUs 14, as illustrated in FIG. 2.The uplink BIC 76 is configured to receive and combine outgoing oruplink RF signals from the RAUs 14 and split the uplink RF signals intoindividual inputs 70 as a return communication path.

The downlink BIC 74 is connected to a midplane interface card 78 panelin this embodiment. The uplink BIC 76 is also connected to the midplaneinterface card 78. The downlink BIC 74 and uplink BIC 76 can be providedin printed circuit boards (PCBs) that include connectors that can plugdirectly into the midplane interface card 78. The midplane interfacecard 78 is in electrical communication with a plurality of opticalinterface cards (OICs) 80, which provide an optical to electricalcommunication interface and vice versa between the RAUs 14 via thedownlink and uplink optical fibers 16D, 16U and the downlink BIC 74 anduplink BIC 76. The OICs 80 include the E/O converter 28 in FIG. 1 thatconverts electrical RF signals from the downlink BIC 74 to optical RFsignals, which are then communicated over the downlink optical fibers16D to the RAUs 14 and then to client devices. The OICs 80 also includethe O/E converter 36 in FIG. 1 that converts optical RF signalscommunicated from the RAUs 14 over the uplink optical fibers 16U to theHEU 12 and then to the outputs 72.

The OICs 80 in this embodiment support up to three (3) RAUs 14 each. TheOICs 80 can also be provided in a PCB that includes a connector that canplug directly into the midplane interface card 78 to couple the links inthe OICs 80 to the midplane interface card 78. The OICs 80 may consistof one or multiple optical interface cards (OICs). In this manner, theHEU 12 is scalable to support up to thirty-six (36) RAUs 14 in thisembodiment since the HEU 12 can support up to twelve (12) OICs 80. Iffewer than thirty-six (36) RAUs 14 are to be supported by the HEU 12,fewer than twelve OICs 80 can be included in the HEU 12 and plugged intothe midplane interface card 78. One OIC 80 is provided for every three(3) RAUs 14 supported by the HEU 12 in this embodiment. OICs 80 can alsobe added to the HEU 12 and connected to the midplane interface card 78if additional RAUs 14 are desired to be supported beyond an initialconfiguration. A head-end unit controller (HEU) 60 can also be providedthat is configured to be able to communicate with the DL-BIC 74, theUL-BIC 76, and the OICs 80 to provide various functions, includingconfigurations of amplifiers and attenuators provided therein.

It may be desired to provide localization services in the opticalfiber-based distributed communications system 10 illustrated in FIGS. 1and 2, as an example. For example, it may be desired to know ordetermine the location of client devices 24. Localization services maybe desired or required to provide certain services, such as emergency911 (E911) services in the case of a cellular client device.Localization services may require a certain percentage of client devices24 to be locatable within a given distance to comply with requirements.For example, it may be desired or required by E911 services to be ableto locate a given percentage of all client device users within onehundred (100) feet (ft.) as an example. Localization services may bedesired or required for other types of wireless clients other thancellular clients as well. If the client device 24 is located inside thebuilding infrastructure 40 and establishes communication with the HEU12, it can be determined that the client device 24 is located within atleast the distance between the farthest RAU 14 located from the HEU 12.However, it may not be possible to determine the location of the clientdevice 24 with greater specificity and resolution. For example, inindoor environments, global positioning services (GPSs) provided in theclient devices 24 may be inoperable to report a location.

If it could be determined to which particular components in the opticalfiber-based communication system 10 a client device 24 establishescommunications, this information could be used to determine the locationof a client device 24. The client device 24 would be known to be withincommunication range of such component. This information coupled withknowing the location of the HEU 12 can be used to determine or provide amore precise area of location of the client device 24. In essence, theRAUs 14 provide another layer of location determination in addition tothe location of the HEU 12. Cellular networks, for example, providemethods of determining location.

In this regard, certain embodiments are disclosed herein to provide anoptical fiber-based distributed communications system that supportslocalization services for client devices located within antenna coverageareas created by RAUs. In certain embodiments disclosed herein, theclient device is configured to include client device identificationinformation as uplink communication data to the RAU and to the HEU andnetwork connected thereto without receiving a tracking signal or othersignal configured to provide localization services. For example, GlobalSystem for Mobile Communications (GSM) network compatible client devicesare configured to automatically initiate providing client deviceidentification information over the network. The locations of the RAUsin the system are also configured and known in the HEU. By knowing andcorrelating the particular RAU in which the client device establishedcommunication, the HEU is able to determine and/or provide the locationof the client device as being within the antenna coverage area formed bythe particular RAU. The correlation of client device identificationinformation from the client device with the location of the RAU isretained when communicated to the HEU and is not lost by being combined,such as by splitters or containers, with communications from other RAUs.

In other embodiments, a signal used for determining the location ofclient devices (also referred to herein as “tracking signal”), and whichmay also be referred to as a pilot signal, beacon signal, or pilotbeacon signal, is distributed by an HEU to at least one of the RAUs inan optical fiber-based distributed communications system. The trackingsignal may be generated by a tracking signal generator or pilot orbeacon generator as examples. The tracking signal is a unique signalthat can be associated with a particular location or zone in the opticalfiber-based distributed communications system. For example, in a codedivision multiple access (CDMA) network, cell identification is includedin a channel separate from communications traffic that can be used as atracking signal. In this manner, the tracking signal is radiated throughthe RAU to be communicated to client devices within range of the antennacoverage area formed by the RAU. When the client device wirelesslyreceives the tracking signal, the client device communicates itsidentification information and identification of the tracking signal toan RAU to be communicated back to the HEU. The HEU can provide thisinformation to a network or carrier. In this manner, the client deviceidentification information and identification of the tracking signal canbe associated with the location of a particular RAU that received andtransmitted the tracking signal in the optical fiber-based distributedcommunications system to provide or determine a location of the clientdevice.

In this regard, FIG. 4 illustrates a schematic diagram of an exemplaryoptical fiber-based distributed communications system 90 that isconfigured to communicate tracking signals TS1-TS4 from an HEU 91 tocertain tracking RAUs 94A-94D to provide localization services. Thetracking RAUs 94A-94D can contain the same components and configurationas the RAUs 14. Thus, this configuration of the optical fiber-baseddistributed communications system 90 employs a tracking signal providedon downlinks to the RAUs 94A-94D to provide localization services. Thedifference is that the tracking RAUs 94A-94D are communicatively coupledto channels or links provided by the HEU 91 that are dedicated to carrya tracking signal. Each tracking signal TS1-TS4 has a uniqueidentification from the other tracking signals TS1-TS4 in thisembodiment. The tracking RAUs 94A-94D selected to receive trackingsignals TS1-TS4 can be strategically located within different trackingzones 96 in a building 98 or other infrastructure. For example, FIG. 4illustrates four tracking zones 96A-96D. Each tracking zone 96A-96D mayrepresent a floor within the building 98 wherein a tracking RAU 94A-94Dis located on each floor. In this embodiment, the tracking signal is notused for communications, and the client devices can receive the trackingsignal from the tracking RAUs 94A-94D over a greater distance thancommunications. Thus, when client devices are located within range of aparticular tracking RAU 94A-94D, the client device will receive theparticular tracking signal TS1-TS4 designated for the floor communicatedto the tracking RAU 94A-94D. The client device can then communicateclient device identification information regarding the received trackingsignal TS1-TS4 back to the HEU 91 and over a network 100. Thus, theparticular floor in which the client device is located can be providedor determined. Note that although the example of tracking illustratesfour (4) tracking zones 96A-96D, the disclosure herein is not limited toproviding a particular number of tracking zones or tracking RAUs placedin the tracking zones to receive and wireless transmit a tracking signalto client devices.

With continuing reference to FIG. 4, other communications RAUs 102A-102Dthat are not configured to receive and wirelessly transmit the trackingsignals TS1-TS4 are also provided in the optical fiber-based distributedcommunications system 90. In this embodiment, these communications RAUs102A-102D form antenna coverage areas in each of the tracking zones96A-96D that are not associated with providing tracking signals orlocation services. The communications RAUs 102A-102D are like the RAUs14 previously described and illustrated in FIGS. 1 and 2 that providedownlink network communications to client devices in range of theantenna coverage areas and receive wireless communications from theclient devices to communicate uplink communication data back to the HEU91 and over the network 100. More than one communications RAU 102A-102Dmay be provided in a given zone 96A-96D to provide communicationsbetween client devices inside the building 98 and the network 100.

As also illustrated in FIG. 4, the tracking RAUs 94A-94D could also beconfigured to transmit downlink communication data to client devices inaddition to the tracking signals TS1-TS4. For example, tracking RAU 94Dis configured to receive both tracking signal TS3 and downlinkcommunication data from the HEU 91 and transmit both to client devicesin range of the tracking RAU 94D. When the client device in range of thetracking RAU 94D receives the tracking signal and the downlinkcommunication data, the client device can transmit client deviceidentification information and uplink communication data back to the HEU91 and over the network 100. The tracking RAU 94D may be configured toreceive uplink communication data from a client device, or may beconfigured to only transmit the tracking signal and downlinkcommunication data to a client device. In the latter case, a secondcommunications RAU 102D located in proximity to the tracking RAU 94D maybe configured to receive the client device identification informationand uplink communication data from the client device to provide to theHEU 91 and the network 100.

As previously discussed and illustrated in FIG. 3, the HEU 12 includesthe downlink BIC 74 that combines downlink electrical RF signalsreceived from the inputs 70. Further, the HEU 12 combines uplinkelectrical RF signals received from the OICs 80 carrying uplinkinformation received by the RAUs 14 and then splits the combined uplinkelectrical RF signals out into individual outputs 72. Thus, if the HEU12 in FIG. 3 were employed as the HEU 91 in FIG. 4 to provide thetracking signals TS1-TS4 to provide localization services, theuniqueness of the tracking signals TS1-TS4 would be lost and thus couldnot be used to associate the location of client devices to particularRAUs 14 to provide localization services. This is because the downlinkBIC 74 would split the tracking signals TS1-TS4 into copies andcommunicate the copies of the tracking signals TS1-TS4 to each of theRAUs 14 instead of particular RAUs 14. Thus, client devices couldreceive tracking signals TS1-TS4 in any of the tracking zones 96A-96D inFIG. 4, as an example.

Embodiments disclosed herein can include modified HEUs that provideexemplary solutions to uniquely provide tracking signals on downlinks tocertain designated tracking RAUs without copies of the tracking signalsbeing communicated to each RAU. The tracking signals are not combinedwith the RF communication signals for communication traffic. The clientdevices can receive the tracking signal from individual tracking RAUsindependent of RF communication signals and the uniqueness ofassociating particular client device identification information receivedfrom a client device to a particular tracking RAU is not lost, and thusthe location of the client devices relative to tracking RAUs can bedetermined and/or provided.

In this regard, FIG. 5A illustrates a schematic diagram of an exemplaryembodiment of an alternative HEU 110 that is configured to providetracking signals to RAUs 14 without splitting the tracking signals intocopies that are distributed to multiple RAUs 14. The HEU 110 can beprovided as the HEU 91 in FIG. 4. Thus, the association of a trackingsignal to a particular RAU 14 is not lost as is the case in the HEU 12of FIG. 3, where the downlink BIC 74 splits the downlink electrical RFsignals into copies provided to each RAU 14. The HEU 110 does includesome common components to the HEU 12 illustrated in FIG. 3. Where commoncomponents are included, common element numbers are used in FIG. 5A.

With continuing reference to FIG. 5A, the downlink BIC 74 of the HEU 12of FIG. 3 has been removed so that tracking signals TS1-TS3 provided asinputs to the inputs 70 do not get split into copies provided tomultiple tracking RAUs 94. The tracking signals TS1-TS3 are provided todedicated tracking RAUs 94 so that a client device receiving a giventracking signal TS1-TS3 is known to be within the antenna coverage areaof the tracking RAU 94 dedicated to receive a given tracking signalTS1-TS3. The HEU 110 is also configured to receive communication signalsCS (FIG. 6) to be provided to communications RAUs 102 that are not usedto receive and communicate the tracking signals TS1-TS3, as alsoillustrated in FIG. 4. In response to receipt of a tracking signalTS1-TS3 from a tracking RAU 94, a client device can return its clientdevice identification information over the uplink optical fibers 16U tothe HEU 110. In this regard, it is known that the client device iswithin the antenna coverage area of the tracking RAU 94 receivingcommunications from the client device. Thus, this information can beretained by the HEC 60 in the HEU 110 and/or provided to the network 100(FIG. 4) to determine and/or provide the location of the client deviceas being within the antenna coverage area of the tracking RAU 94.

In the example HEU 110 of FIG. 5A, three tracking signals TS1-TS3 areprovided as inputs to three inputs 70; however, more or less trackingsignals could be provided. The electrical RF signals received in theinputs 70 may be provided to a signal power leveling module 112 to levelthe power between different signals provided to different inputs 70, ifdesired. However, the tracking signals TS1-TS3 are not combined or splitin the signal power leveling module 112. A connector panel 114 may alsobe provided in the HEU 110 to receive the electrical RF signals from theinputs 70 and provide a connection to OICs 80 to convert the electricalRF signals to optical RF signals, as previously discussed. The signalpower leveling module 112 and OICs 80 may be disposed, for example, inprinted circuit board (PCB) cards that can be plugged into connectorsdisposed in the connector panel 114 to connect the outputs and inputs ofthe signal power leveling module 112 to the inputs and outputs,respectively, of the OICs 80. The connector panel 114 may also be a PCBcard that contains circuitry or other components.

FIG. 5B illustrates a schematic diagram of an exemplary embodiment of analternative HEU 110′ that is configured to provide tracking signals toRAUs 14 also without splitting the tracking signals into copies that aredistributed to multiple RAUs 14. Thus, the association of a trackingsignal to a particular RAU 14 is not lost as is the case in the HEU 12of FIG. 3. The HEU 110′ does include some common components to the HEU12 illustrated in FIG. 3. Where common components are included, commonelement numbers are used in FIG. 5B.

With continuing reference to FIG. 5B, radio interface modules (RIMs)113(1)-113(N) are provided that receive the downlink electrical RFsignals from the inputs 70 to provide RF communications services. Thenotations “1-N” indicate that any number of the RIMs, 1-N, may beprovided. Each RIM 113(1)-113(N) may support RF communication servicesfor given frequencies or frequency ranges or bands. The downlinkelectrical RF signals are then combined in a radio distribution card orcards (RDC) 115 to be provided to the OIMs 80 and the RAUs 94, aspreviously discussed. The RIMs 113(1)-113(N) are configured to receiveand process downlink electrical RF signals from the inputs 70 prior tooptical conversion into downlink optical RF signals.

Each RIM 113(1)-113(N) can be designed to support a particular type ofradio source or range of radio sources (i.e., frequencies) to provideflexibility in configuring the HEU 110′ to support the desired radiosources. For example, one RIM 113 may be configured to support thePersonal Communication Services (PCS) radio band. Another RIM 113 may beconfigured to support the Long Term Evolution (LTE) 700 radio band. Inthis example, by inclusion of these RIMs 113, the HEU 110′ would beconfigured to support and distribute RF signals on both PCS and LTE 700radio bands. RIMs 113 may be provided in the HEU 110′ that support anyother radio bands desired, including but not limited to PCS, LTE, CELL,GSM, CDMA, CDMA2000, TDMA, AWS, iDEN (e.g., 800 MHz, 900 MHz, and 1.5GHz), Enhanced Data GSM Environment, (EDGE), Evolution-Data Optimized(EV-DO), 1×RTT (i.e., CDMA2000 1× (IS-2000)), High Speed Packet Access(HSPA), 3GGP1, 3GGP2, and Cellular Digital Packet Data (CDPD). Morespecific examples include, but are not limited to, radio bands between400-2700 MHz including but not limited to 700 MHz (LTE), 698-716 MHz,728-757 MHz, 776-787 MHz, 806-824 MHz, 824-849 MHz (US Cellular),851-869 MHz, 869-894 MHz (US Cellular), 880-915 MHz (EU R), 925-960 MHz(TTE), 1930-1990 MHz (US PCS), 2110-2155 MHz (US AWS), 925-960 MHz (GSM900), 1710-1755 MHz, 1850-1915 MHz, 1805-1880 (GSM 1800), 1920-1995 MHz,and 2110-2170 MHz (GSM 2100).

With continuing reference to FIG. 5B, note that the tracking signalsTS1-TSN are not provided to the RDC 115 where the tracking signalsTS1-TSN are combined and split, but rather are provided to dedicatedtracking RAUs 94 so that a client device receiving a given trackingsignal TS1-TSN is known to be within the antenna coverage area of thetracking RAU 94 dedicated to receive a given tracking signal TS1-TSN. Inthis regard, HEU 110′ is also configured to receive communicationsignals CS (FIG. 6) to be provided to communications RAUs 102 that arenot used to receive and communicate the tracking signals TS1-TSN. Inresponse to receipt of a tracking signal TS1-TSN from a tracking RAU 94,a client device can return its client device identification informationover the uplink optical fibers 16U to the HEU 110′. In this regard, itis known that the client device is within the antenna coverage area ofthe tracking RAU 94 receiving communications from the client device.Thus, this information can be retained by the HEC 60′ in the HEU 110′and/or provided to the network 100 (FIG. 4) to determine and/or providethe location of the client device as being within the antenna coveragearea of the tracking RAU 94. In the HEU 110 of FIG. 5A, both thedownlink BIC 74 and uplink BIC 76 from the HEU 12 of FIG. 3 were removedfrom both the tracking signal TS and communication signal CScommunication paths through the HEU 110 to the RAUs 94, 102. However, itis not necessary to remove the downlink BIC 74 and the uplink BIC 76from the communication signals CS communication paths. In the HEU 110′of FIG. 5B, the tracking signals TS1-TSN were not combined and splitwith downlink RF signals in the RDC 115. In this regard, FIG. 6illustrates a schematic diagram of an exemplary alternative HEU 120 thatis configured in a hybrid configuration. FIG. 7 illustrates thefunctionality of the HEU 120 provided in two separate HEUs 120A, 120B,each dedicated to either handle tracking signals TS or communicationsignals CS. The HEUs 120A, 120B are provided in an optical fiber-baseddistributed communications system 130 wherein RAUs 94, 102 aredistributed in different floors of a building 132 similar to the opticalfiber-based distributed communications system 10 in FIG. 2. One trackingRAU 94(1)-94(N) is provided for each floor 134(1)-134(N) in the building132.

With reference back to FIG. 6, some communication paths are dedicatedfor tracking signals TS1-TSN and other communication paths are dedicatedfor communication signals CS1-CSN. In this regard, separate connectionpanels 122A, 122B are provided for each type of communication path forthe HEUs 120A, 120B. The downlink BIC 74 and uplink BIC 76 are employedin the communication signal CS1-CSN communication paths in the HEU 120Ato split copies of the communication signals CS1-CSN to be provided tothe communications RAUs 102, as described previously and illustrated inthe HEU 12 of FIG. 3. Alternatively in FIG. 6, RIMs may be employed inlieu of the downlink BIC 74 and uplink BIC 76. In this example, thedownlink BIC 74 and uplink BIC 76 are not employed in the trackingsignal TS1-TSN communication paths in the HEU 120B such that copies ofthe tracking signals TS1-TSN are not provided to multiple tracking RAUs94, otherwise the ability to associate the tracking signals TS1-TSN to aparticular tracking RAU 94 would be lost in this embodiment.

The tracking RAUs 94 and communications RAUs 102 may be provided asseparate RAUs or may be configured to share components. For example, atracking RAU 94 may be co-located with a communications RAU 102 andshare the same antenna. In this regard, FIG. 8 illustrates an fiberoptic cable 138 comprised of downlink optical fibers 16D and uplinkoptical fibers 16U connected to one or more OICs 80. In this embodiment,a tracking RAU 94 is provided that is co-located with a communicationsRAU 102, as illustrated in FIG. 8. In this regard, the tracking RAU 94and communications RAU 102 may be configured to share some commoncomponents. For example, in this embodiment, the tracking RAU 94 andco-located communications RAU 102 share a common, single antenna 140. Apower combiner 141 is provided to combine electrical RF signalstransmitted from both the tracking RAU 94 and communications RAU 102 fordownlink communications and to split uplink communication signalstransmitted from client devices to the antenna 140 destined for thetracking RAU 94 and the communications RAU 102. Alternatively, theuplink communication signals may not be split between the tracking RAU94 and the communications RAU 102. Both the tracking RAU 94 andcommunications RAU 102 may receive all uplink communication signals fromclient devices in range of the antenna 140 and communicate the signalsback to the HEUs 120A, 120B. The HEUs 120A, 120B can employ filters orother processing techniques to separate the uplink communication signalsfrom the uplink client device identification information, if needed ordesired.

FIG. 9 illustrates a schematic diagram of an exemplary embodiment of anHEU 142 with a port configuration to separate tracking signals inputsfrom communication signal inputs. In this regard, separate ports 143 areprovided to receive tracking signals TS1-TSN from tracking signalgenerators to provide to tracking RAUs 94. The tracking signals TS1-TSNbypass the downlink BIC 74, the uplink BIC 76, and a connection panel144 and are connected directly to ports in OICs 150. This can allow oneHEU 142 to be provided to distribute both the tracking signals TS1-TSNand communication signals CS1-CSN instead of providing two separateHEUs, like provided in FIGS. 6 and 7. In this embodiment, the trackingsignals TS1-TSN are combined with communication signals CS1-CSN in anOIC 80 that is configured to receive both signals. The combined trackingsignals TS1-TSN and communication signals CS1-CSN are communicated tothe tracking RAU 94 and the communications RAU 102. This implementationdoes not have the location resolution on a per RAU basis that would beprovided if the tracking signals TS1-TSN were not combined in the OICs150 with the communication signals CS1-CSN. The location resolution isper OIC 150 instead of per RAU 94, 102 in this embodiment. However,separate HEUs are not required in this embodiment. Further, the powersignal levels between the tracking signals TS1-TSN and the communicationsignals CS1-CSN can be varied relative to each other.

FIG. 10 illustrates an example of an OIC 150 that may be provided aspart of the OIC 80 in FIG. 9 to provide one solution to prevent thetracking signal received by the OIC 150 from being sent to allcommunications RAUs 102 supported by the OIC 150 so that trackinginformation is not lost. In this embodiment, an OIC 150 is provided andis comprised of a single PCB to support up to three (3) RAUs in thisembodiment; however, this configuration is not required and the numberof supported RAUs is not limiting. For example, two OICs 150 coupled beprovide in a single optical interface module (OIM) to support up to six(6) RAUs in this embodiment. The OIC 150 is illustrated with onedownlink port 152 and one uplink port 154. The downlink port 152provides the combined downlink electrical RF signals from the downlinkBIC 74 to the OIC 150 to convert such downlink electrical RF signals todownlink optical RF signals to communicate over the downlink opticalfibers 16D to communications RAUs 102, as illustrated in FIG. 9. Asplitter 156 splits the downlink RF signals into multiple copies to beprovided to each of the communications RAUs 102 supported by the OIC150. The uplink port 154 receives uplink electrical RF signals that areconverted from uplink optical signals received from the communicationsRAUs 102. The uplink electrical RF signals are combined via a combiner158 and passed to the uplink port 154 to be communicated to the uplinkBIC 76.

In the OIC 150 of FIG. 10, the OIC 150 has been modified and adapted tobe used to allow a tracking signal to be communicated to allcommunications RAUs 102 supported by the OIC 150 to provide a per-OIClocation resolution. In this manner, a completely new design for the OIC150 is not required. In this regard, a downlink tap 153 is provided inthe OIC 150 to allow a tracking signal generator 155 to bypass thedownlink BIC 74 to provide a tracking signal TS directly to the OIC 150.The tracking signal TS is communicated through the splitter 156 suchthat a copy of the tracking signal TS is provided to each RAU 94, 102supported by the OIC 150. Thus, the location information provided bydistribution of the tracking signal TS will only allow locationdetermination on the resolution of the OIC 150 and not on a per RAUbasis since the tracking signal is provided to all RAUs 94, 102supported by the OIC 150. A downlink communication signal can also becommunicated to the OIC 150 through the downlink port 152 to alsoprovide communication signals to the RAUs 94, 102. The tracking signalTS and downlink communication signals will be split by the splitter 156into copies provided to each RAU 94, 102.

Similarly, an uplink tap 160 is provided to bypass the uplink BIC 76provided in an HEU so that client device identification informationreceived from the RAUs 94, 102 is not combined with other uplinkcommunication signals from other HEUs. The client device identificationinformation received from the RAUs 94, 102 is combined by the combiner158; thus, location information provided by distribution of the trackingsignal TS in this embodiment will only allow location determination onthe resolution of the OIC 150 and not on a per RAU basis.

FIG. 11 illustrates an alternative OIC 170 that has also been modifiedand adapted to allow a tracking signal from a tracking signal generatorand returned client device identification information from RAUs tobypass the downlink BIC 74 and the uplink BIC 76 like provided in theOIC 150 in FIG. 10. However, in the OIC 170 of FIG. 11, locationdetermination can be provided on a per RAU basis instead of a per OICbasis. This is because downlink taps 172 for receiving tracking signalsand uplink taps 174 for receipt of returned client device identificationinformation are provided separately for each RAU 94, 102 supported bythe OIC 170. In this embodiment, because the OIC 170 supports three (3)RAUs 94, 102, three (3) downlink taps 172 and three (3) uplink taps 174are provided. The downlink taps 172 and uplink taps 174 are providedafter the splitter 156 and combiner 158 so that the tracking signal isnot copied to multiple RAUs 94, 102, and so that returned client deviceidentification information from the RAUs 94, 102 is not combined. Inthis embodiment, the OIC 170 can receive up to three (3) tracking signalgenerators 155A-155C to provide unique tracking signals to each RAU 94,102. Likewise, the client device identification information returned bythe RAUs 94, 102 to the OIC 170 can be individually provided to three(3) separate outputs 72A-72C.

Further, as used herein, it is intended that terms “fiber optic cables”and/or “optical fibers” include all types of single mode and multi-modelight waveguides, including one or more optical fibers that may beupcoated, colored, buffered, ribbonized and/or have other organizing orprotective structure in a cable such as one or more tubes, strengthmembers, jackets or the like. Likewise, other types of suitable opticalfibers include bend-insensitive optical fibers, or any other expedientof a medium for transmitting light signals. An example of abend-insensitive, or bend resistant, optical fiber is ClearCurve®Multimode fiber commercially available from Corning Incorporated.Suitable fibers of this type are disclosed, for example, in U.S. PatentApplication Publication Nos. 2008/0166094 and 2009/0169163.

Many modifications and other embodiments of the embodiments set forthherein will come to mind to one skilled in the art to which theembodiments pertain having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. These modificationsinclude, but are not limited to, whether a tracking signal is provided,whether downlink and/or uplink BICs are included, whether trackingsignal inputs are provided in the same distributed communicationsapparatus as downlink inputs, the number and type of OICs and RAUsprovided in the distributed communications system, etc. Therefore, it isto be understood that the description and claims are not to be limitedto the specific embodiments disclosed and that modifications and otherembodiments are intended to be included within the scope of the appendedclaims. It is intended that the embodiments cover the modifications andvariations of the embodiments provided they come within the scope of theappended claims and their equivalents. Although specific terms areemployed herein, they are used in a generic and descriptive sense onlyand not for purposes of limitation.

What is claimed is:
 1. A method for providing localization services in adistributed communications system, comprising: configuring at least onedistinct location zone in the distributed communications system, whereinthe at least one distinct location zone comprises a tracking remoteantenna unit (RAU); providing at least one tracking signal to thetracking RAU in the at least one distinct location zone, wherein the atleast one tracking signal carries an identification of the at least onetracking signal that identifies the at least one distinct location zone;broadcasting the at least one tracking signal from the tracking RAU;receiving an uplink radio frequency (RF) communications signal from aclient device located in the at least one distinct location zone,wherein the uplink RF communications signal comprises client deviceidentification information and the identification of the at least onetracking signal; and locating the client device based on the clientdevice identification information and the identification of the at leastone tracking signal.
 2. The method of claim 1, further comprisinggenerating the at least one tracking signal from a tracking signalgenerator or a pilot generator or a beacon generator.
 3. The method ofclaim 1, further comprising receiving the uplink RF communicationssignal from the client device without providing the at least onetracking signal to the tracking RAU in the at least one distinctlocation zone, wherein the uplink RF communications signal comprises theclient device identification information.
 4. The method of claim 1,further comprising not splitting or combining the at least one trackingsignal.
 5. The method of claim 1, further comprising communicativelycoupling the tracking RAU to channels dedicated to carry the at leastone tracking signal.
 6. The method of claim 5, further comprisingreceiving the client device identification information from the clientdevice after communicating the at least one tracking signal.
 7. Themethod of claim 5, further comprising receiving the client deviceidentification information from the client device without communicatingthe at least one tracking signal.
 8. A method for configuring adistributed communications system to provide localization services,comprising: configuring at least one distinct location zone in thedistributed communications system, wherein the at least one distinctlocation zone comprises a plurality of remote antenna units (RAUs);identifying and configuring a tracking RAU among the plurality of RAUs;providing a distributed communications apparatus in the distributedcommunications system, further comprising: configuring at least onefirst downlink input to receive downlink radio frequency (RF)communications signals, wherein the downlink RF communications signalsare configured to carry downlink communication data; configuring atleast one second downlink input to receive at least one tracking signalidentifying the at least one distinct location zone; and configuring atleast one uplink output to receive and communicate uplink RFcommunications signals from a communications uplink, wherein the uplinkRF communications signals carry client device identification informationand an identification of the at least one tracking signal identifyingthe at least one distinct location zone; and configuring the trackingRAU in the at least one distinct location zone to receive and transmitthe at least one tracking signal identifying the at least one distinctlocation zone.
 9. The method of claim 8, further comprising configuringthe tracking RAU to transmit the at least one tracking signal and thedownlink communication data carried in the downlink RF communicationssignals.
 10. The method of claim 8, further comprising associating theclient device identification information to a location of the trackingRAU.
 11. The method of claim 10, further comprising not splitting orcombining the uplink RF communications signals received from thetracking RAU with the uplink RF communications signals received fromanother RAU among the plurality of RAUs.
 12. The method of claim 8,further comprising communicatively coupling the tracking RAU to channelsdedicated to carry the at least one tracking signal.
 13. The method ofclaim 12, further comprising receiving the client device identificationinformation from a client device after communicating the at least onetracking signal.
 14. The method of claim 12, further comprisingreceiving the client device identification information from a clientdevice without communicating the at least one tracking signal.
 15. Adistributed communications system for providing localization services,comprising: at least one distinct location zone in the distributedcommunications system, wherein the at least one distinct location zonecomprises a tracking remote antenna unit (RAU); and a distributedcommunications apparatus configured to: provide at least one trackingsignal to the tracking RAU in the at least one distinct location zone,wherein the at least one tracking signal carries an identification ofthe at least one tracking signal that identifies the at least onedistinct location zone; broadcast the at least one tracking signal fromthe tracking RAU; receive an uplink radio frequency (RF) communicationssignal from a client device located in the at least one distinctlocation zone, wherein the uplink RF communications signal comprisesclient device identification information and the identification of theat least one tracking signal; and locate the client device based on theclient device identification information and the identification of theat least one tracking signal.
 16. The distributed communications systemof claim 15, wherein the distributed communications apparatus is furtherconfigured to generate the at least one tracking signal from a trackingsignal generator or a pilot generator or a beacon generator.
 17. Thedistributed communications system of claim 15, wherein the distributedcommunications apparatus is further configured to receive the uplink RFcommunications signal from the client device without providing the atleast one tracking signal to the tracking RAU in the at least onedistinct location zone, wherein the uplink RF communications signalcomprises the client device identification information.
 18. Thedistributed communications system of claim 15, wherein the distributedcommunications apparatus is further configured not to split or combinethe at least one tracking signal.
 19. The distributed communicationssystem of claim 15, wherein the tracking RAU is communicatively coupledto channels dedicated to carry the at least one tracking signal.
 20. Thedistributed communications system of claim 19, wherein the distributedcommunications apparatus is further configured to receive the clientdevice identification information from the client device aftercommunicating the at least one tracking signal.
 21. The distributedcommunications system of claim 19, wherein the distributedcommunications apparatus is further configured to receive the clientdevice identification information from the client device withoutcommunicating the at least one tracking signal.